PCT Application WO 99/21748 discloses an end module assembly for installation on the front or rear end of a partially completed motor vehicle and a method for making the same. While WO 99/21748 broadly discloses the end module assembly concept and methods for constructing end module assemblies with properly aligned exterior components, further efforts and developments have revealed certain improvements to enhance the end module assembly's functional performance and the aesthetic appearance of the resulting vehicle.
The end module assembly (front or rear) is intended to be assembled separately from the remainder of the vehicle and then subsequently shipped to the OEM (original equipment manufacturer) for installation on a partially completed motor vehicle. As a result, this introduces the potential for errors either in the vehicle frame assembly or in the end module assembly that can lead to the end module assembly and its exterior fascia being misaligned with respect to the remainder of the vehicle when installed. Misalignment between the module assembly's exterior fascia and the remainder of the body assembly is not acceptable because it detracts significantly from the vehicle's overall aesthetic appearance and requires correction before the vehicle can leave the assembly site.
In both the arrangement disclosed in WO 99/21748 and in conventional vehicle constructions, the bumper beam is fastened to the frame assembly at the end of the vehicle. Normally, this connection is at the ends of the frame rails. This is done so that collision forces received by the bumper beam will be transmitted to the frame assembly, which is more robust and better suited for absorbing collision forces than the body assembly. When dealing with vehicles in which relative movement is permitted between the frame and body assemblies, ample space must be provided to ensure that the bumper beam does not contact the vehicle body assembly, especially the fascia panels, during such relative movement. This is to prevent the bumper beam from damaging body assembly components as the vehicle is being driven over rough terrain. In pick-up trucks and sport utility vehicles, this space for accommodating the bumper beam's movement manifests itself as a visible gap between the exterior bumper cover and the fascia at the front end of the vehicle.
For end module assemblies that mount on vehicles in which relative movement is permitted between the vehicle frame assembly and the vehicle body assembly, WO 99/21748 discloses the end module assembly as mounting on round rubber blocks for movement along with the body assembly relative to the vehicle frame assembly. The bumper beam is carried loosely within the module assembly and then attached separately to the vehicle frame assembly. This requires separate brackets for loosely carrying the bumper beam and additional assembly steps to ensure that the bumper beam is securely fastened to the vehicle frame assembly.
In the end module assembly of WO 99/21748, the engine is assembled to the vehicle separately from the end module assembly and then the engine is connected to the various power-operated systems in the end module assembly and throughout the remainder of the vehicle. Making these connections requires a number of assembly steps and then testing is required to ensure that the systems in the vehicle are connected and functioning properly.
For vehicles of varying heights and/or widths, the exterior fascia and the internal support structure must be sized to fit properly on the vehicle. Specifically, the height and width of each internal support structure must be chosen for proper fit on the vehicle for which it was designed. One way to accomplish this would be to have separate tools that have been customized to form the components of each internal support structure to predetermined sizes so that the resulting support structures are properly sized for the vehicle on which they are to be installed. Using separate sets of tools for each type of end module assembly, however, is very costly and requires a great deal of factory space and the workers necessary to run each tool.